initdb failure on Windows 2003

I’m trying to install Postgres 8.4.9.1 on a Windows 2003 SP2 64bit
operating system. The download has installed previously (to a windows 7
box) so I know it should be OK but under W2003 the initdb command seems to
be failing. It doesn’t return an error message but non of the actions are
performed, the data directory remains empty.

Any ideas, or extra logging that I can switch on to try and tie this down.
I can’t reproduce it on a W2003 box running the 32bit OS and getting hold
of another 64 bit box is complicated.

The install log looks like:

Called CreateDirectory(D:\Mingle\PostgreSQL\8.4\data)...

Called CreateDirectory(D:\Mingle\PostgreSQL\8.4)...

WScript.Network initialized...

Called IsVistaOrNewer()...

'winmgmts' object initialized...

Version:5.2

MajorVersion:5

Ensuring we can write to the data directory (using cacls):

Executing batch file 'rad38351.bat'...

Executing batch file 'rad38351.bat'...

Reading: objConfFile is nothing...

Writing: objConfFile is nothing...

We’ve also tried with 8.3 and 9.1 installers and get exactly the same
result.

Any help of hints would be most appreciated.

Regards,

Mike Wylde